We researched different lenses in an effort to improve the viewability of outer edges and corners of larger (3") LCD screens. We found a lens that will mount in the original ClearViewer and gives a sharp view of even the corners of the 3" LCD screens often used on newer cameras.

Note, with the standard convex lens (top left), when viewing at a sharp angle to see the corners of the LCD screen, the light must travel farther through both curves of the glass than when viewing the central area of the screen.

Also note that the distance from lens to LCD is much farther when viewing the corners than it is to the center of the LCD, making it more difficult to have both the center area and the outside edges in focus. Diopter lenses have a very limited in-focus range.

With the premium plano-convex lens, the side of the lens facing the eye is flat, resulting in less distance the light must travel through the glass; and the result is less distortion for those corners.

Because there's a single curved surface, the lens can more easily be shaped to allow the further distances of the corners and edges to be in focus along with the center. Improved optical qualities of the glass also help reduce distortion at those sharper angles.

If your camera has a 2 3/4" or 3" LCD, it may be a wise choice to pick the premium lens. The clear veiw of the entire LCD screen aids in composition, and in viewing subjects at or near the edges of the photo.

Measure your LCD screen from corner-to-corner, diagonally, and if it's 3" (75mm) or nearly that size, consider the premium lens as a good investment.